Salt-lovers :
immense bloom of a halophilic ("salt-loving") archaean species at a salt
works near San Quentin, Baja California Norte, Mexico. This archaean,
Halobacterium, also lives in enormous numbers in salt ponds at the south
end of San Francisco Bay; interested residents of this area should take the
Dumbarton Bridge for the best views.

Archaeans include inhabitants of some of the most extreme environments
on the planet. Some live near rift vents in the deep sea at temperatures
well over 100 degrees Centigrade. Others live in hot springs, in extremely
alkaline or acid waters, or in extremely saline water. These
pictures show an immense bloom of a
halophilic ("salt-loving"; dependent on high salt concentrations)
archaean species, in a saline pond at a salt
works near San Quintin, Baja California Norte, Mexico.
This archaean, Halobacterium,
also lives in enormous numbers in salt ponds at the south end of
San Francisco Bay; interested residents of this area should take the
Dumbarton Bridge for the best views. An interesting fact about
Halobacterium is that the red light-sensitive pigment that gives
Halobacterium its color, which is a simple photosynthetic system
that provides the archaean with chemical energy, is known as
bacteriorhodopsin -- and is chemically very similar
to the light-detecting pigment
rhodopsin, found in the vertebrate retina.

Read about undersea black smoker vents at the American Museum of Natural History's Black Smokers page.

The Microbe Zoo features several methane-producing organisms, including some Archaea.

For more information on Halobacteria, including lesson information for teachers, go to The HaloEd Project.

Pictures of Norm Pace and Pyrodictium courtesy Norm Pace and the Dept. of Plant Biology at UC Berkeley. Picture of black smoker by Prof. Iver Duedall at Florida Tech, and courtesy the Norm Pace Lab.
Images of methanogens on ciliate, chemostat, and Methanosarcina kindly provided by the Dept. of Microbiology, University of Nijmegen, The Netherlands.